Pinpointing ADHD Symptoms in Children with Down Syndrome

Published May 2021 | Journal of Developmental and Behavioral Pediatrics

Attention-deficit hyperactivity disorder (ADHD) is the most common neurobehavioral disability, impacting between 6% and 8% of kids in the general population. Yet ADHD may be as high as 20% to 44% among people with Down syndrome (DS). Despite this increased prevalence, diagnosis of ADHD among kids with Down syndrome can pose a true challenge.

“It is difficult to tell if many of the problematic behaviors—such as difficulty focusing, forgetfulness, and avoidance of effortful tasks—are due to intellectual disability or if children with DS also have ADHD,” says senior author Tanya Froehlich, MD, director of research, Division of Developmental and Behavioral Pediatrics.

Research led by Froehlich and first author Anna Esbensen, PhD, found several differences in how parents and teachers report potential symptoms of ADHD that varied depending on whether the child had DS.

Parents of kids with DS and ADHD tended to report more distractibility and being “on the go,” while teachers tended to report higher inattention and hyperactivity as compared to kids with DS only or typically developing children with ADHD. Some teacher-reported items specifically differentiated DS + ADHD and DS - ADHD, including difficulties following through on tasks, avoiding tasks, leaving one's seat, and excessive talking.

Overall, the reporting variations highlight a need to evaluate across environments when diagnosing for ADHD. More consistent differentiation of symptoms would help clinicians determine which children with DS can benefit from ADHD treatment. Looking ahead, the team is evaluating how children with DS and ADHD respond to methylphenidate, the most common ADHD drug.

ADHD Comparison between Children with and without Down Syndrome

Comparison between children who have DS with and without ADHD, and typically developing (TD) children with ADHD on the Vanderbilt ADHD Diagnostic Parent Rating Scale and Vanderbilt ADHD Diagnostic Teacher Rating Scale.